The present invention relates to satellite-based communications. More specifically, the present invention relates to techniques for increasing the utilization of available communication channels assigned to a satellite.
For many years, landline telecommunications carriers have adopted an on-peak/off-peak billing strategy for telecommunications. xe2x80x9cOn-peakxe2x80x9d is typically the period of time in the business day during which there is a high volume of telecommunications taking place. Accordingly, the landline carriers charge full price for long distance communications during this on-peak period. In contrast, xe2x80x9coff-peakxe2x80x9d is typically the period of time after the business day has ended during which business communications drop sharply and residential calling builds. The landline carriers typically offer discounted rates on long distance telecommunications during this off-peak period to encourage utilization of the landline telecommunications system during these low usage periods and to discourage utilization of the landline telecommunications system for residential calls during the higher usage periods.
Likewise, many cellular communications system carriers also have adopted an on-peak/off-peak billing strategy for telecommunications. Typically, off-peak rates may be available for cellular calls between 7:00 p.m. and 7:00 a.m. in a given geographical area, and on weekends and holidays. The goal is to encourage more cellular calls during typical periods of low activity, so as to more efficiently utilize the frequency spectrum, or communication channels, assigned to a particular cellsite. In other words, the off-peak period can be construed as a xe2x80x9cpreferred communications periodxe2x80x9d from the perspective of the subscriber since the airtime rates are lower. Furthermore, since there is lower utilization of the frequency spectrum, the subscriber""s call is more likely to be successfully allocated a communication channel.
In conventional land-based cellular communications systems, the on-peak/off-peak periods generally follow a predictable pattern since land-based cellular systems have cell sites at fixed, spaced apart locations. Thus, once the call activity pattern is determined in a fixed location, or a cell, served by the cell site, the preferred communications period and the corresponding discounted rate can be established for that particular geographical location.
This established preferred communications period (i.e., off-peak period) for the particular geographical location can be readily remembered by subscribers. However, since the established preferred communication period is based on a prediction of call activity, the actual call activity may differ. In other words, there may be pockets of low call activity during on-peak periods, and there may be pockets of high call activity during off-peak periods.
Conventional on-peak/off-peak periods cannot adapt to these unexpected pockets of low or high activity.
In a satellite-based communication system that provides world-wide or near world-wide radio communications service through a plurality of orbiting base stations, i.e., satellites, the conventional on-peak/off-peak periods for a particular satellite coverage zone are not as predictable as the conventional land-based system. The larger size of a satellite""s footprint, or coverage zone, as opposed to the size of a cell in a land-based cellular system gives rise to a greater number of variables when attempting to predict on-peak/off-peak call activity periods. Such variables include satellite orbital dynamics, holidays specific to particular cultures, differing business hours in different countries receiving radio communications services in the same satellite coverage zone, variances in the quantities of subscriber units in different countries within the same satellite coverage zone, and so forth. These variables significantly complicate the predictions. In addition, on-peak/off-peak periods established in response to the complicated predictions can be difficult for the subscribers to remember.
One strategy for providing incentives to potentially increase cellular calling during low activity periods in a satellite-based communication system could entail the acquisition of predictable on-peak/off-peak activity data of the satellite-based cellular network in much smaller geographical locations within a give satellite coverage area. This data could be stored, for example, in a billing center in order to apply on-peak or off-peak airtime rates to particular calls. Unfortunately of data required to effectively initiate such a multiple rate billing strategy could lead to a vastly complicated and expensive billing program and to subscribers unaware of changes made in response to dynamic conditions. Moreover, such a strategy is not able to adapt to unexpected periods of low cellular activity as they arise.
Satellite-based communication systems that provide world-wide or near world-wide radio communications service are becoming more pervasive because they offer great mobility. That is, the subscriber may place and receive calls from anywhere in the world and may generally move without restriction from one satellite radio communications coverage zone to another while using the satellite-based communication system. Unfortunately, when a strategy such as that described above has been adopted, a subscriber who travels extensively does not necessarily know when on-peak and off-peak rates take effect in the differing geographical locations in which the subscriber may travel. Accordingly, traveling subscribers would not necessarily be motivated to utilize the satellite-based communication systems during low activity periods.
Thus, what is needed is a system and method for potentially increasing call activity in a satellite-based communication system that detects low call activity periods as they arise and informs subscriber units of these low activity periods.